I am going to be getting a 97 4x4 ext cab 5sp. with 113,000 miles. I am familiar with the cummins as I had a 24v. This truck has never been turned up. If I adust the starwheel and slide the fuel plate, and advancing the timing a little, and adjusting the valves on it, will I possibly pick up a little extra mpg? I already plan on putting on either a cold air intake or a high flow air filter and removing the cat/muffler and straight piping it out the back or putting stacks on it. I dont need huge power and drive with a very mild foot. Im out for a mpg rig. Any other ideas? Thanks!